delta 4 medium
The Delta IV Medium (Delta 9040) is the most basic Delta IV. It features a single CBC and a modified Delta III second stage, with 4-meter liquid hydrogen and liquid oxygen tanks and a 4-meter payload fairing derived from the Delta III fairing. The Delta IV Medium is capable of launching 4,210 kg (9,285 lb) to geosynchronous transfer orbit (GTO).
The Delta IV Medium+ (4,2) (Delta 9240) is similar to the Medium, but uses two Alliant-built 1.5-m (60-in) diameter solid rocket strap-onGraphite-Epoxy Motors (GEM-60s) to increase payload capacity to 5,845 kg (12,890 lb) to GTO.
The Delta IV Medium+ (5,2) (Delta 9250) is similar to the Medium+ (4,2), but has a 5-m–diameter payload fairing for larger payloads and a modified second stage with a 5-meter liquid hydrogen tank and stretched liquid oxygen tank. Because of the extra weight of the larger payload fairing and second stage, the Medium+ (5,2) can launch 4,640 kg (10,230 lb) to GTO, less than the Medium+ (4,2).
The Delta IV Medium+ (5,4) (Delta 9450) is similar to the Medium+ (5,2), but uses four GEM-60s instead of two, enabling it to lift 6,565 kg (14,475 lb) to GTO.
The Delta IV Medium+ (4,2) (Delta 9240) is similar to the Medium, but uses two Alliant-built 1.5-m (60-in) diameter solid rocket strap-onGraphite-Epoxy Motors (GEM-60s) to increase payload capacity to 5,845 kg (12,890 lb) to GTO.
The Delta IV Medium+ (5,2) (Delta 9250) is similar to the Medium+ (4,2), but has a 5-m–diameter payload fairing for larger payloads and a modified second stage with a 5-meter liquid hydrogen tank and stretched liquid oxygen tank. Because of the extra weight of the larger payload fairing and second stage, the Medium+ (5,2) can launch 4,640 kg (10,230 lb) to GTO, less than the Medium+ (4,2).
The Delta IV Medium+ (5,4) (Delta 9450) is similar to the Medium+ (5,2), but uses four GEM-60s instead of two, enabling it to lift 6,565 kg (14,475 lb) to GTO.
